Found my surging idle demon

Posted By: Carsavior

Found my surging idle demon - 02/18/14 08:27 AM

65 New Yorker with a 413 and a Holley 600 carb. Car would idle up and down. Played with jetting, changed out power valve, block vacuum advance- all without any changes to the surging. Today I had the hood up listening to my surging beauty, Noticed I would hear a click right before it would idle up. Click-vroom. Click-vroom. Traced the sound to the- PCV valve. Pulled the valve, blocked the hose, and the surging stopped! Haven't run into a mystery PCV valve problem since the Plymouth Trouble Shooting contest years ago. Ordered a new valve online tonight. Hope that clears it up for good!

Posted By: RapidRobert

Re: Found my surging idle demon - 02/18/14 04:22 PM

Quote:

Hope that clears it up for good!

I believe it will. You sure wouldn't suspect the PCV as the culprit for a vac leak & I've only ran into that once (it stuck wide open), tho the PCV is a controlled vac leak & from what I understand different ones have a different size orifice.

Posted By: Cab_Burge

Re: Found my surging idle demon - 02/18/14 07:12 PM

I like to use a PCV valve with a weak spring so it stays open anytime the motor is running

Helps lean the idle out also in motors with big cams